how to create a singleton with Io

 1rl@bloodandguts:~/github/io$ io
 2Io 20090105
 3Io> Highlander := Object clone
 4==>  Highlander_0x1957db0:
 5  type             = "Highlander"
 6
 7Io> Highlander clone := Highlander
 8==>  Highlander_0x1957db0:
 9  clone            = Highlander_0x1957db0
10  type             = "Highlander"
11
12Io> h := Highlander clone
13==>  Highlander_0x1957db0:
14  clone            = Highlander_0x1957db0
15  type             = "Highlander"
16
17Io> h type
18==> Highlander
19Io> h
20==>  Highlander_0x1957db0:
21  clone            = Highlander_0x1957db0
22  type             = "Highlander"
23
24Io>